In transport systems for mould-string casting plants of this kind it is known to effect the transport by means of the pressure plate expelling the formed moulds from the moulding machine and supplementary mechanical means in the form of movable longitudinal side rails applying a positive lateral force on each side of the mould string and moving in an advancing and longitudinal stepwise manner synchronised with the movement provided by the pressing plate of the moulding machine, said mechanical means being positioned close to the moulding machine for gripping the moulds immediately after leaving said moulding machine. A transport system of this kind is known from U.S. Pat. No. 3,744,552.
Another supplementary mechanical means for providing the forward movement of the mould string comprises an array of equally spaced, parallel, rigid rails extending in the direction of the movement of the mould string from the moulding machine. The array of equally spaced rails comprises fixed rails and movable rails, said movable rails being moved by mechanical and hydraulic means and positioned between the fixed rails in an alternate manner, the movable rails being moved in a cyclic manner synchronised with the movement provided by the pressing plate of the moulding machine, said cyclic movement of the movable rails comprising lifting the movable rails to support the mould string, moving one step forward, lowering the movable rails leaving the mould string supported on the fixed rails, and moving the movable rails back to their initial position ready to be lifted again to support the mould string in order to minimise the vertical movement of the moulds and reduce the friction, the so-called fixed rails are lowered during the forward movement of the movable rails. A transport system of this kind is known from DE-2,311,253.
It is furthermore known to provide a belt conveyor for performing the final transport of the mould string towards the knock-out station, said belt conveyor being positioned to receive the mould string after sufficient solidification of the mouldings, whereby the precision of the transport is less significant for obtaining precision mouldings.
In connection with modern moulding machines having a high production rate, the distance over which the mould string has to be transported before reaching the knock-out station increases and furthermore, the distance over which the precision conveyance of the mould string is essential for obtaining precision mouldings by avoiding dislocation of individual mould parts relative to one another, is also increasing. Accordingly, there exists a demand for extending the high-precision part of the transport system as well as the total length of the transport system.